1. Field of the Invention
The invention relates generally to linear polymers that can be cured to form high temperature elastomers and plastics, and in particular to a high temperature elastomer made by curing linear poly(silarylene-siloxane-acetylene).
2. Description of the Related Art
The aerospace industry has a continuing demand for high performance materials that can withstand extreme variations of temperatures. In particular, there is a need for materials that have elastomeric properties, that have thermal, thermo-oxidative and hydrolytic stability at high temperatures (as high as 300-350° C.) and that maintain their flexibility below ambient temperatures. For example, fuel tanks of high flying airplanes and space vehicles require sealants that maintain elasticity for up to 10,000 hours of use at temperatures that range from −60° C. to 400° C. Further, the material must resist swelling when coming into contact with jet fuel and must have excellent adhesion to and inertness toward metallic substrates.
Linear polymers and crosslinked polymers that have repeating units made up of diacetylene groups and siloxane groups are disclosed in, for example, U.S. Pat. No. 5,563,181 to Keller et al and U.S. Pat. No. 5,874,514 to Keller et al, both incorporated herein by reference.
Linear polymers and crosslinked polymers and copolymers made up of silarylene and siloxane units are disclosed in, for example, U.S. Pat. No. 5,578,380 to Babu, U.S. SIR No. H1612 to Rhein et al, and U.S. Pat. No. 5,346,980 to Babu, all incorporated herein by reference.